The invention relates to an apparatus for playing back information digitally stored on an optical record carrier, comprising
a control circuit by means of which the display and/or reproduction of information, particularly video and/or audio information, is selectable and/or controllable, PA1 a parameter memory for storing navigation parameters during playback of a record carrier.
An apparatus of this type is known from, for example, WO 98/09290. This known apparatus is provided for playing back digital video record carriers. To control the display of the audio and/or video program, the known apparatus has navigation commands and navigation parameters. Generally, those parameters are understood to be navigation parameters whose information is stored by the playback apparatus during the playback process. The navigation parameters comprise, for example, parameters to which a predetermined function is assigned and also parameters which can be freely used by the provider and are, for example, usable for modifying the behavior of the playback apparatus or for storing the user-performed operations, decisions and/or wishes. Navigation commands and navigation parameters are the basis for providers of record carriers for creating different title structures. The providers can use the navigation commands and navigation parameters for adjusting or changing the status of the playback apparatus, for example, for implementing a parental control system which denies children access to predeterminable video programs.
The provider can define simple and complex branch structures in a title by means of the navigation commands and the navigation parameters.
The navigation parameters of record carriers based on the DVD standard are set to zero at the start and the end of a playback process of a record carrier. The navigation parameters of record carriers in accordance with the HQ-Video CD (High Quality Video Compact Disc) standard are undefined at the start and at the end of the playback process.